1. Field of the Invention
The present invention relates to a medical device for intubating a patient, and more particularly to a dual-bladed laryngoscope.
2. Description of the Related Art
It is often necessary to put a tube in a person's airway for assisting in breathing, such as emergency situations where a patient or victim is no longer able to breath normally, or during anesthesia or cardiac arrest to prevent aspiration of mucus, vomit, or particulate matter into the lungs. This procedure is referred to as endotracheal intubation. A laryngoscope may be used to assist a caregiver in performing this procedure. Laryngoscopes may be comprised of a single blade, which may be straight or curved for guiding the tube into the trachea, or comprised of two blades. A dual-bladed laryngoscope has two opposing blades that are connected by a pair of hinge points, and each blade has a handle in proximate relationship to each other for opening distal ends of the blades which then open a passageway through a patient's mouth and larynx into which an endotracheal tube may be passed. Laryngoscopes are often fitted with a light for illuminating the passageway for easier insertion of the laryngoscope and the intubation tube.
The intubation process is often difficult due to anatomic or pathologic differences between individuals. The most common error in intubation is placing the tube in the esophagus instead of the trachea when the caregiver cannot adequately see the trachea or vocal cords. Failure to recognize this error can lead to fatal hypoxia in an intubated patient, and some studies have shown a failure rate of up to 30% for intubations made in the field.
In an effort to minimize this failure rate, some laryngoscopes include fiber optics for visualizing the vocal cords for proper tube placement, however these devices are very expensive and are not widely available. Other devices have been developed as alternatives to endotracheal intubation, such as the Esophogeal Obturator Airway (EOA), the Esophagogastric Tube Airway (EGTA), the Esophageal Tracheal Combitube, and the Laryngeal Mask Airway (LMA). These devices are designed to allow “blind” intubation without the operator actually visualizing the vocal cords and trachea. The EOA lacks proven effectiveness and is considered dangerous by design. The EGTA is a variant of the EOA and suffers from the same drawbacks. It was a predecessor to the Combitube. Regarding the Combitube and the LMA, experts maintain that these devices should only be used temporarily until definitive airway management can be achieved through endotracheal intubation. Therefore, there is still work to be done in simplifying the endotracheal intubation process and ensuring proper and definitive airway management.
U.S. Pat. No. 5,498,231, issued to Franicevic on Mar. 12, 1996, is incorporated by reference for all purposes, including alternatives and equivalents for various elements of the presently claimed invention. The Franicevic invention is directed to a laryngoscope comprising an elongate hollow body consisting of two hollow tubes with a pair of opposed blades pivotally mounted to the distal end of the hollow body. These blades are perpendicular to the hollow body and pivotal on their axes so that the blades may assume an open or closed position. A complicated rack and pinion gear system is used to open the blades. An endotracheal tube can be passed through the hollow body and between the blades via a tube introducor. A sophisticated steering mechanism allows the tube introducer to steer the endotracheal tube into the trachea. A fiberoptic optical system with illumination is provided for observation during the intubation procedure. The primary disadvantage of this art is that the fiber optics and complicated design make it very expensive. Another disadvantage is that you must disassemble the endotracheal tube by removing the proximal fitting that connects the tube to an oxygen source in order to remove the laryngoscope, and there is no mechanism for blocking the esophagus to ensure proper tube placement in the trachea. In addition, the design of this laryngoscope makes it impossible to suction the patient without removing the entire laryngoscope first. This wastes valuable seconds when trying to establish a patent airway for a patient.
U.S. Pat. No. 5,938,591, issued to Minson on Aug. 17, 1999 provides a good review of the prior art on laryngoscopes and is incorporated by reference for all purposes, including alternatives and equivalents for various elements of the presently claimed invention. Minson describes a disposable, curved, dual-bladed laryngoscope with light conductive blades that open and lock apart laterally and/or radially. The blades are separated and locked apart using a ratchet mechanism in the handle that allows the device to be self-retaining in the airway. However, other than illuminating the airwary, this device provides no other assistive mechanisms to increase the ease and accuracy of intubation. In addition, in order to suction a patient, a suction device must be passed through the laryngoscope first and then removed before the endotracheal tube can be inserted into the airway. If the patient vomits before the endotracheal tube is properly inserted, the tube must be removed, a suction device inserted, used, and removed, and then the endotracheal tube reintroduced through the laryngoscope. This exchanging of tubes can waste valuable seconds when seconds really count. Minson also teaches that the laryngoscope may be left in the throat after the endotracheal tube is placed in the trachea. If this occurs, his laryngoscope will have to be removed during the time one oxygen source is exchanged for another. This could add precious seconds to the time a patient is without oxygen during this exchange.
The following U.S. Pat. Nos. claim areas of innovations in laryngoscopes: U.S. Pat. Nos. 4,314,551; 4,384,570; 4,517,964; 5,993,383; 6,095,972; 6,174,281; 6,217,514; 6,231,505; 6,354,993; 6,471,643 and RE 37,861. However, these devices do not include features to decrease the likelihood of missed intubation, they are difficult to remove after insertion of the endotracheal tube, and they lack the ability to easily suction the patient using the same hand as the one holding the laryngoscope. In fact, none of the related art contains these features, all of which could improve the likelihood of proper tube placement and simplify the intubation process for the caregiver.
While there are suction devices that are operated independently of a laryngoscope, there are none that are integral to the laryngoscope itself. While U.S. Pat. No. 5,595,172 issued to Reese on Jan. 21, 1997, teaches suction through an endotracheal tube operated by a finger, this device is separate from the laryngoscope and in fact functions as a stylet for the endotracheal tube. This device is operated using the right hand while the left hand holds the laryngoscope. Once the endotrachreal tube is in place, the suction mechanism must be removed from the tube while keeping the tube stabilized with the right hand and still holding the laryngoscope with the left hand. This process is awkward and unwieldy.